<p>oh whew… thanks.</p>
<p>Hah, sorry =P. anyone remember any others? For some reason its reassuring knowing if I got them right or not…</p>
<p>You just gave me a heart attack. I thought I had screwed up somewhere. Jeez.</p>
<p>By the way…what do you guys think the curve will be like this year? 81-85 for an 800, or what? I didn’t really think it was too hard, but I don’t know…</p>
<p>im hoping lenient …</p>
<p>Does anyone know what the raw # of questions for a 720-780 usually is around?</p>
<p>I think the question about the amphoteric substance was very unfair. Both C and D would’ve worked. NH3 can donate a proton to become NH2-, or receive one to becoem NH4+. And of course HCO3- is. So can someone clarify here?</p>
<p>I think water is a stronger acid than NH3 so NH3 isn’t likely to give up a proton in water. Not sure though…</p>
<p>there was definitly no product graph question…i have no recolection of such a thing</p>
<p>Hmm so I am predicting about 9 wrong. Out of curiousity does CB publish the curve after they publish scores?! or what.</p>
<p>I clearly remember graphs on both solubility and product concentration…</p>
<p>Alright first of all, CuSO45H2O is WHITE, CuSO4 by itself is BLUE. The NH3 compound was the blue one.</p>
<p>The one about H2S was TF because it said H2S was polar but it said it had ONE pair of electrons, it has TWO.</p>
<p>The one about PF3 was TTCE, it is trygonal pyramidal, and the pairs create mutual repulsion.</p>
<p>The Cd question was Cd(OH)2. Cd can only have an oxidation state of +2 so that just proves it.</p>
<p>I thought that test was quite easy, I don’t know about you guys…</p>
<p>mmm no CuSO4*H2O is blue</p>
<p><a href=“http://images.google.com/images?hl=en&q=CuSO4•5H2O&btnG=Search+Images&gbv=2[/url]”>http://images.google.com/images?hl=en&q=CuSO4•5H2O&btnG=Search+Images&gbv=2</a></p>
<p>sorry iradeon but you are thinking of the anhydride, which is white.</p>
<p>No, its white and the anhydride was the one on the test.</p>
<p>…you said your self CuSO4•5H2O was on the test (not an anhydride…), which is blue</p>
<p>Oh god, CuSO4•5H2O IS the anhydride. I got a 99 in AP Chem and I know what I am talking about.</p>
<p>I’m pretty sure that CuSO4•5H2O is indeed blue.</p>
<p>Hah, exactly. CuSO4•5H2O = hydrate, CuSO4= anhydrous</p>
<p>Iradeon
… 99 is a good mark… congratulations!
it has been a long day but check your colours and definitions
hubris can kill ya</p>
<p>Don’t be so full of yourself… -I’m- in AP Chem, too, and we did a lab with the hydrated copper sulfate. It starts out blue, but when it is heated, it gradually loses its blue color and fades to white BECAUSE the water is evaporating! ANhydride = “a compound formed by removing water from a more complex compound.” Straight from the dictionary… there’s no arguing with Merriam Webster.</p>